"The immune system is like a double-edged sword; it can fight cancer but also needs to be controlled."

最成功的领导者是那些将领导视为责任而非特权的人。

可持续性不仅仅是一个流行词，它是负责任林业的基础。我们必须在经济增长和环境管理之间取得平衡。

The Government of the United States is a definite Government, confined to specified objects. It is not like the state governments, whose powers are more general.

The secondary rules are those that provide for the creation, alteration, and extinction of primary rules.

学习数学的最好方法就是做数学。